There shouldn't be a problem for Sitefinity to work with large sites that have a lot of data. We have some clients that are working with such web site and they do not have complaints regarding Sitefinity.
However note that we have a bug logged connected to permissions. If you have more that 30 administrators, when you click Change button in the Permissions section you will receive and error: "Object, object". The only thing you need to add is the following line in your web.config file:
Note that if you have 250 administrators the
might need to be changed to a bigger number.
Please inform us if there are some problems. We will be glad to help you.
the Telerik team
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